Liquid contact switch for controlling plural circuits



G. A. RILEY April 11, 1967 LIQUID CONTACT SWITCH FOR CONTROLLING PLURAL CIRCUITS Filed June 10, 1965 2 Sheets-Sheet 1 INVENTOR.

HTTORNEYS G. A. RILEY April 11, 1967 LIQUID CONTACT SWITCH FOR CONTROLLING PLURAL CIRCUITS Filed June 10, 1965 2 Sheets-Sheet 2 .HTTORNFYS.

United States Patent ()fifice 3,313,903 Patented Apr. 11, 1967 3,313,903 LIQUID CONTACT SWITCH FOR CONTROLLING PLURAL ClRCUlTS George Albert Riley, Bridgeport, Conan, assignor to Harvey Hubbell, Incorporated, Bridgeport, Conn., a corporation of Connecticut Filed June 10, 1965, Ser. No. 462,916 11 Claims. (Cl. 200152) The present invention relates to liquid contact switches and particularly to an improved mercury button switch of the type which is widely used for controlling residential lighting circuits.

The mercury button switch element commonly used in many prior art mercury electrical switch assemblies is a single throw liquid contact switch, which will hereinafter he referred to as a mercury button. It is employed in an electrical mercury switch assembly, hereinafter referred to as a mercury switch, to manually selective-1y either open or close one side of an electrical power supply line. In a single pole mercury switch, a single mercury button is usually employed and arranged to selectively either open or close a power line between the two usual screw terminals of a single pole switch to thereby either illuminate or extinguish the electrical lamp. As the usual mercury button is a single throw switch element, it is necessary to employ two mercury buttons in a double pole mercury switch or in a threeway mercury switch. In a three-way mercury switch, the wiring is such that one terminal of each of the mercury buttons is commonly wired to one side of the power line and functions as an input terminal; the other terminal of each mercury button is individually connected to a separate output conductor, and the mercury buttons are oriented in the mercury switch so that one is open when the other is closed. Sheldon et al. Patent 3,109,- 079, is exemplary 0115 a three-way mercury switch employing two mercury buttons. In prior art tf our-way mercury switches, it has been necessary hereto-fore to employ four mercury buttons and a complicated actuating linkage assembly. The patents to Sambleson 2,142,151 and Hutt 2,290,641 are exemplary of prior art four-wire mercury switches employing four buttons and complex linkage assemblies.

Patents such as Payne 2,101,093, Walker 2,101,114 and Navias 2,153,000 are exemplary of single throw mercury buttons of the type employed in all of the referred-to mercury switches of the prior art. Such single throw mercury buttons have usually included a disk-like ceramic barrier sandwiched between a pair of spaced cup-shaped metal shell terminals, frequently made of chrome iron. The assembly of these elements is such as to form an enclosure which is hydrogen filled to a pressure of approximately three atmospheres and hermetically sealed by a glass ring encircling the adjacent rims of the shell terminals and bonded to the periphery of the ceramic barrier. A small axial through-opening is formed through the barrier to connect spaces on opposite sides thereof at a point that is radially oiiset from the geometric center of the barrier, which center coincides with the pivotal axis of the mercury button. A quantity of mercury is disposed within the enclosure of the button to move within the enclosure in a controlled manner as a liquid contact medium for selectively electrically connecting the two metal shell terminals to close the switch circuit through the mercury button. This is accomplished when the mercury button is rotated to immerse the through-opening in the barrier into the pool of mercury so that the mercury, that was previously separated by the barrier into two spaced pools on opposite sides of the barrier, flows through the throughopening and merges into one pool of mercury that is in contact with both shell terminals. To open the circuit through the mercury button the procedure is reversed, and the mercury button is rotated in the opposite direction to lift the through-opening out of the mercury, thereby electrically isolating the mercury into two separate spaced pools on opposite sides of the barrier.

Mercury switches employing the foregoing type of single throw mercury button have achieved substantial commercial success and are in widescale usage, particularly as components in residential lighting circuits. One of their major attributes is that of silent operation in switching, particularly as contrasted with snap toggle switches. Although superior to most other electrical switches in this regard, such as mechanical snap-acting toggling switches, mercury switches have not been employed to the extent they might, because of their relatively high cost. The cost of the mercury button itself constitutes one of the largest elements of cost in a mercury switch. As pointed out above, one mercury button is used in a single pole mercury switch; however, it is necessary to employ two mercury buttons in a three-way switch and four mercury buttons with an expensive linkage assembly in a four-way switch. Not only does the necessity of incorporating plural mercury buttons in three-way and four-way mercury switches add materially to their cost, but they additionally create a need for sufiicient physical space in the mercury switch to house the mercury buttons, and this results frequently in the three-way and four-way mercury switches being too bulky for utilization in many practical applications where they might otherwise be utilized.

It is an object of this invention to provide an improved liquid contact switch of the mercury button type wherein the mercury button is capable of double-throw operation,

which makes it possible to employ only one double-throw mercury button in a three-way mercury switch and requires only two double-throw mercury buttons in a fourway switch, and in the latter instance eliminates the need for complicated and expensive actuating linkage assembly heretofore utilized in four-way mercury switches.

The object of this invention is achieved in one form by providing a liquid contact switch which is similar in shape and size to a prior art single-throw mercury button, but includes an assembly of an internal insulation disk-like barrier means within two cup-shaped conducting metallic shell terminals that form an enclosure with three diametrical spaces within the mercury button, an axial middle space and two axial end spaces; and a central electrical conducting terminal that extends diametrically through the barrier means from the exterior of the enclosure to the interior of the middle space and has a portion projecting therein; the barrier means being formed to provide two diametrically displaced axial through-openings each individually disposed to connect the middle space with one of the end spaces; the overall arrangement being such that the central electrical terminal functions as a common electrical lead that is arranged to be selectively electrically connected to either shell terminal by a pool of mercury disposed within the spaces and contacting the central terminal portion and one of the shell terminals, dependent upon the angular position of the mercury button.

The above and other objects and advantages of this invention will become apparent from a consideration of this specification and the drawings wherein:

FIG. 1 comprises a side elevational view, with portions broken away and shown in section for clarity, of a mercury button incorporating the invention;

FIG. 2 is a sectional view taken substantially on line 2-2 of FIG. 1;

FIGURE 3 is an exploded View of the mercury button of FIG. 1;

FIG. 4 is a sectional view taken substantially on line 4-4 of FIG. 1 of the improved mercury button and an actuating handle;

FIGS. 5, 6 and 7 are schematic views showing the mercury button in association with an actuating handle in different angular switch settings;

FIG. 8 is a plan view of a three-way mercury switch embodying the invention with portions broken away for clarity;

FIG. 9 is a side elevational view thereof with portions broken away for clarity;

FIG. 10 is a plan view of a four-way mercury switch embodying the invention with the cover removed, and

FIG. 11 is a perspective view of an actuating handle usable with the improved mercury buttons.

In FIGS. 1, 2 and 3 of the drawings there is illustrated a liquid contact element by itself which incorporates the invention. Herein it will be referred to for convenience as a mercury button and because of the common usage in the art of this nomenclature. It should be understood, however, that the invention is not limited to the utilization of mercury, as a liquid contact medium, though this is the preferred material presently contemplated for use as the liquid electrical contact conducting material. The mercury button is designated generally by reference character B and is of the same general shape and size as existing mercury buttons. It comprises a pair of opposed juxtaposed shallow dished metallic electrical conducting members 2 and 4 which are designated shell terminals and are similar except that the shell terminal 2 has a small opening therein that is useful in manufacture; a refractory material insulating barrier means in the form of a pair of recessed and apertured disk-like members 6 and 8 which are similar in construction; a central metallic washer-like electrical conducting contact dis-c -a metal weld 12 closing the opening 5, and an annular ring 14 of glass, suitable plastic material or the like which joins the peripheries of the shell terminals 2 and 4, the barrier members 6 and 8 and the contact disc 19 in an hermetically sealed manner to thereby form a unitary mercury button having a uniquely formed internally chambered enclosure.

As can best be seen in FIG. 3, the contact disc 10 includes a peripheral contact shoe formation 34 to be subsequently described and a plurality of arcuate slots 16 adjacent its periphery which permit the glass of which the sealing ring 14 is formed to flow through the disc 10 to provide an effective bond between the shell terminals, barrier members and contact disc to form a unitary mercury button assembly. The barrier members 6 and 8 are similar in formation and comprise disc-like members having circular recesses 6a and 8a, respectively, formed in an axial side thereof which oppose each other when the mercury button is fully assembled, and circular recesses 6b and 8b on their other respective sides. Each barrier member has an eccentrically disposed axially transverse through-opening 6c and 8c respectively, which places its respective recesses into communication. When the mercury button is fully assembled, the through-openings 6c and 8c are eccentrically disposed relative to the axis of the completed mercury button and diametrically aligned on opposite sides of the said axis.

As can best be seen in FIG. 2, the fully assembled mercury button forms an enclosure having the following characteristics as a result of the configuration and dimensions of the various elements of which it is made: three internal mercury storage spaces are formed, comprising a middle space 18, and end spaces 20, 22 on opposite sides of the middle space; middle space 18 is formed by opposed recesses 6a and 8a; through-opening 6c in barrier member 6 interconnects the middle space 18 with end space 20; through-opening 8c in barrier member 8 interconnects middle space 18 with end space 22; end spaces 20 and 22 are formed respectively between recesses 6b and 8b and the adjacent inner surfaces of shell terminals 2 and 4, and the washer-like contact disc 10 includes a central opening 24, and the rim portion 26 of disc 10 about said opening extends into the middle space 18 and is concentrically disposed about the axis of the mercury button in position to always contact liquid disposed thereon regardless of the angular position of the mercury button.

The interconnected spaces in the mercury button enclosure have disposed therein a quantity of mercury which in operation selectively forms a plurality of pools and functions to contact and close an electrical circuit through the washer-like disc contact member 10 and either the shell terminal 2 or 4 in certain angular positions of the mercury button. The spaces in the mercury button are preferably filled with hydrogen or another suitable arcsuppressing gas at a pressure in the order of three atmospheres, the opening 5 being utilized to inject the mercury and gas into the spaces in manufacture of the mercury button, but thereafter being sealed by the weld plug 12.

In FIG. 4 the mercury is shown in phantom lines in three separate pools in the spaces 18, 20, 22, each pool being designated by the reference numeral 28. -In the condition of the mercury button illustrated in FIG. 4, none of the circuits through the mercury button is closed, as the pools 28 of mercury are three disconnected pools in the three spaces in the mercury button. This is the condition illustrated schematically in FIG. 5, wherein it will be observed that the through-openings 6c and 8c are both above the upper levels of the pools of mercury 28 and, therefore, the barrier members 6 and 8 effectively separate the mercury into three separate pools, no one pool being in con-tact with both the rim portion 26 of washerlike contact disc 10 and either of the shell terminals 2 or 4.

The contact disc 10, which functions as a common electrical lead, may be selectively manually electrically connected through the mercury to either of the shell terminals 2 or 4, by rotation of the mercury button in one angular direction or the other. Starting with FIG. 5 as schematically illustrating the position of the mercury button when on all circuits are open, which condition is also shown in FIG. 4, it will be observed that an actuating handle 32 may be operatively associated with the mercury button B. Shell terminals 2 and 4 each have at least one indentation 2a, 4a, respectively, in which an actuating lug 30 on the actuating handle 32 may be disposed to rotate the mercury button selectively in a controlled manner. An arcuate groove 31 surrounds a portion of ring 14. One peripheral portion of the contact disc 10 ex tends substantially beyond the periphery of the sealing ring 14 and is formed into the previously mentioned con tact shoe 34, which may be arranged to have sliding elec trical engagement with a contact strip 36 which may form a part of a mercury switch assembly.

If it is desired to close the circuit through the contact disc 10 and terminal shell 4, with reference to FIGS. 5, 6 and 7, the handle 32 is actuated so as to move the mercury button counter-clockwise to the position illus trated in FIG. 7. In this position, the pools of mercury 28 in the middle space 18 and the end space 22 join to form a single pool, and the through-opening 3c of the barrier member 8 is immersed in this joined pool of mercury to thereby contact and form an electrical conducting path from a part of the rim portion 26 of contact disc 10 which is immersed in the joined pool of mercury through the pool to the inner surface of the shell terminal 4. In this position, the through-opening 6c in the barrier member 6 is disposed substantially vertically above the through-opening 8c and the level of any pool of mercur, thereby precluding any electrical connection through a pool of mercury of the contact disc 10 and the terminal shell 2. Therefore, the electrical conductor in contact with the sheell terminal 4 and contact strip 36 are electrically connected in this position of the mercury button.

If it is desired to close the circuit between the contact disc 10 and the terminal shell 2, the handle is actuated to rotate the mercury button clockwise to the position illustrated in FIG. 6, wherein it will be observed that the through-opening 6c in the barrier member 6 is disposed below the through-opening 8c and is immersed in the joined pool of mercury 2a; which thereby electrically connects the rim portion 26 of the contact disc and the inner surface of the terminal shell 2. Therefore, the electrical conductor in contact with the shell terminal 2 and contact strip 36 are electrically connected in this position of the mercury button.

The foregoing constitutes a detailed description of the construction and operation of an improved mercury button for controlling dual circuits which embodies my invention. When oriented as illustrated in FIGS. l7, the mercury button may be selectively manually adjusted by rotation between the FIGS. 5, 6 and 7 conditions to close a circuit through contact strip 36 and either shell terminal. The dispositioned relationship in these figures is such as to require the actuating handle 32 to extend vertically upwardly in the circuit open condition (FIG. 5); extend upwardly at an angle to the right to close the circuit through contact strip 36 and shell terminal 2 (FIG. 6), and extend upwardly to the left to close the circuit through contact strip 36 and shell terminal 4 (FIG. 7).

In FIGS. 8 and 9 there is illustrated a three-way mercury switch, by way of example, which incorporates my improveed mercury button. It is contemplated that my improved mercury button will be employed in various and other switch assembly constructions. In FIGS. 8 and 9 the three-way switch is illustrated as comprising a housing 49 of electrical insulation material which is appropriately configured to accommodate one of my improved mercury buttons and three electrical contact strip members. The primary cont-act strip member 42 is a bent metallic strip that is mounted and supported in the housing at? and includes a screw terminal 44 which is accessible from the exterior of the switch housing to permit wiring of an electrical conductor thereto, and an arcuate portion 46, which functionally corresponds to contact strip 36 in FIGS. 4-7 and is in sliding contact with the contact shoe 34 of a mercury button B. The electrical conductor which is wired to the screw terminal 44 comprises one side of the power line and is connected to the common terminal lead formed by the contact disc 1'0. A pair of metallic secondary contact strip members 48 and 50 that are similar in construction, but reversed, are supported by the housing 40 and include screw terminal portions 52, 54 respectively, which are accessible from the exterior of the switch housing on opposite sides thereof for wiring the secondary wires. The contact strip members 48, 50 include ball-like formations 52a and 54a which are disposed within the socket-like cavities formed in opposite sides of the shell terminals 2 and 4, and frictionally engage said terminals to both support the mercury button B between them and to effect individual electrical contact with the terminal shells. The threeway mercury switch disclosed thus far operates in a manner such that the primary contact strip 42 and the screw terminal 44 may be selectively electrically connected to either contact strip 48- or 5% hence their respective screw terminals 52, 54, depending upon the position of the mercury button B. In FIG. 9, the mercury button B is positioned in such a manner that the circuits of both screw terminals 52 and 54 are open, and this corresponds to the schematic position of the mercury button illustrated in FIG. 5. If it is desired to close the circuit between screw terminals 44 and 54, the actuator handle 32 of the switch is moved to one side and this results in rotation of the mercury button B and one of the through-openings in one of the barrier members being immersed within a pool of mercury to thereby place the terminal shell 2 and disc contact 10 into electrical connection. Movement of the actuator handle 58 toward the opposite direction has the effect of oppositely rotating the mercury button and immersing the other throughopening in a pool of mercury and placing the disc contact 10 into electrical connection with the terminal shell 4.

In FIGS. 8 and 9 the three-way switch is shown with a usual mounting yoke 56 secured to housing 40 by screws 58, and the'entire switch is oriented with the yoke in a horizontal plane. The discussion relative to FIGS. 1-7 was similarly related. Although the switch could be mounted in this position, for example if mounted in or to a fiat horixontal surace, in practice it normally would be mounted in a vertical wall so the yoke is disposed in a vertical plane. In the latter orientation, the directional references heretofore made in describing the constructionoperation of the mercury button would have to be translated to account for the difference in angular mounting of the switch.

FIG. 10 schematic-ally illustrates a four-way mercury switch having a housing 59 wherein two of my improved mercury buttons B are employed. The mounting yoke is shown in phantom lines, and an actuator handle 32 as illustrated in FIG. 11 is employed. The contact terminal arrangement is such as to include two primary contact strip members 60, 62, each having a screw-type terminal 60a, 62a to which separate line conductors may be wired and an arcuate portion for engaging the contact shoe of a mercury button; a contact strip member 64 having a double-ball terminal formation 66 engaging the adjacent shell terminals of the two mercury buttons and including a screw terminal 64a; and a cross-over contact strip arrangement comprising the contact strip portions 68 and 69, and having a common screw terminal 70, each of portions 68, 69 having a ball terminal formation portion individually in engagement with an outer shell terminal of one of the mercury buttons. The mercury buttons are disposed and selectively controlled by an actuator handle 32 of the same type required for a conventional three-way mercury switch. When assembled, the handle 32 straddles the adjacent shell terminals of the mercury buttons and has its lugs 36) seated in the adjacent indentations in the shell terminals to effect simultaneously rotation of both mercury buttons by actuation of the handle 32. The result of actuation of the handle 32 is to electrically connect the common disc terminal of the mercury buttons which are electrically connected to the primary contact strip members 60, 62, hence screw terminals 60a, 62a, to either one shell terminal on the same respective sides of the mercury buttons or the shell terminals on the other sides to achieve the operation of 'a four-way switch. The mercury buttons B are angularly mounted to achieve this operation.

In view of the foregoing, it will be apparent that the objects of this invention have been achieved. An improved mercury button has been provided which has the capability of controlling two electrical circuits and, in particular, includes 'a common contact which may be selectively connected to either of two shell terminals. The improved mercury button lends itself to incorporation into three-way and four-way switches. In the former application, it effects three-way switch operation by utilizing only one mercury button as opposed to the requirement for employing two mercury buttons in prior art three-way mercury button switches. In the latter application in a four-way mercury button switch, the objective is achieved by utilizing just two of the improved mercury buttons with a conventional mercury button actuator handle, thereby eliminating both two of the mercury buttons heretofore required in prior art fourway mercury button switches and the complex linkage assembly for mounting and actuating the previously required four mercury buttons. Modifications of this invention will occur to those skilled in this art. It is to be understood, therefore, that this invention is not limited to the particular embodiments disclosed, and that it is intended to encompass all modifications and applications which fall within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A dual circuit controlling electrical switch comprising: a pair of spaced opposed juxtaposed shallow dished shell terminal members of electrical conductive material being electrically separated and connected at their adjacent peripheries by an annular electrical insulating seal to form an enclosure; barrier means of electrical insulating material disposed within said enclosure between said terminal members and cooperating therewith to divide said enclosure into three spaced separate spaces for storage of electrically conductive liquid including a middle space and two end spaces; an electrical conducting termi nal means extending through said barrier means from the interior to the exterior of said enclosure out of contact with said terminal members, said terminal means having a first portion extending into said middle space arranged to be contacted by said liquid and a second portion extending to the exterior of said enclosure and arranged for electrical contact with an electrical conductor; a quantity of electrically conductive liquid disposed in said spaces; and said barrier means having passage means forming a passage extending between said middle space and an end space, and a separate displaced passage extending between said middle space and the other end space; said passages and terminal means being arranged so only one of said passages is immersed in a pool of said liquid in certain angular positions of said switch whereby said liquid electrically connects one terminal member with said terminal means first portion, and the other of said passages is immersed in a pool of said liquid in certain other positions of said switch whereby said liquid electrically connects the other terminal member with said terminal means first portion.

2. The switch of claim 1 which further includes in assembly a housing of electrical insulation material; a pair of electrical contact members supported by said housing and individually electrically connected to said terminal members; a third electrical contact member supported by said housing and electrically connected to said terminal means second portion; and means for selectively angularly positioning said switch in said housing.

3. The switch of claim 2 wherein said terminal members and said contact members have complementary ball and socket portions in frictional engagement whereby said switch is rotatably supported by said contact members about the axis of said terminal members.

4. The switch of claim 2 wherein said third electrical contact member includes an arcuate portion frictionally engaging said terminal means first portion and thereby aiding in the support of said switch.

5. The switch of claim ll wherein said terminal means comprises a centrally disposed washer-like disc having an annular rim portion formed about a central opening extending into said middle space constituting its first portion, and a radially extending arcuate portion extending beyond said enclosure and formed into a contact shoe constituting its second portion.

6. The switch of claim 1 wherein said terminal means includes peripheral portions that extend beyond said barrier means that include perforations that are embedded in said seal.

7. The switch of claim 1 wherein said barrier means comprises a pair of recessed barrier members disposed on opposite sides of said terminal means.

8. A dual circuit controlling electrical switch comprising: a pair of spaced opposed juxtaposed circular shallOW dished shell terminal members of electrical conducting material; a pair of spaced circular disc-like barrier memhers of electrical insulating material disposed between said terminal members and having recessed portions on their sides cooperating therewith to divide said enclosure into three spaced separate parallel spaces including a middle space between opposing sides of said barrier members and two end spaces between the distant sides of said barrier members and the inner surfaces of adjacent terminal members for storage of electrically conductive liquid; a. metallic washer-like contact disc disposed between the opposing sides of said barrier members and having an annular central rim portion extending into said middle space and a radially extending portion extending beyond said barrier members and formed into a contact shoe; the peripheral portions of said terminal members, said barrier members and said washer-like disc being adjacent; an annular seal secured to said peripheral portions thereby forming a unitary switch enclosure; a transverse passage in each of said barrier members, each passage connecting said middle space with a different end space; a quantity of electrically conductive liquid in said spaces; said passages being non-aligned and angularly displaced whereby one of said passages is arranged to be immersed in a pool of said liquid in certain angular positions of said switch to electrically connect one of said terminal members with said central rim portion of said washer-like disc, and the other of said passages is arranged to be immersed in a pool of said liquid in certain other angular positions of said switch to electrically connect the other of said terminal members with said central portion.

9. The electrical switch of claim 8 wherein said contact disc includes a plurality of peripheral perforations and some of the material of said annular seal is disposed in said perforations.

159. A three-way electrical liquid contact switch assembly comprising: a housing of electrical insulation material; a pair of secondary conductor-terminal members; a primary conductor-terminal member; a dual circuit controlling liquid contact switch comprising a pair of juxtaposed spaced opposed shallow dished shell terminal members of electrical conductive material being secured and electrically separated by an electrical insulating seal to form an enclosure; barrier means of electrical insulating material disposed within said enclosure between said terminal members and cooperating therewith to divide said enclosure into three spaced separate spaces for storage of electrically conductive liquid including a middle space and two end spaces; an electrical conducting terminal means extending through said barrier means from the interior to the exterior of said enclosure out of contact with said terminal members, said terminal mean having a first portion extending into said middle space and a second portion extending to the exterior of said enclosure and arranged for electrical contact with an electrical conductor; said barrier means being provided with passage means arranged to connect said spaces in a preselected :manner; a quantity of electrically conductive liquid disposed in said spaces; said passage means forming a passage between said middle space and an end space, and a separate non-aligned angularly displaced passage between said middle space and the other end space; said passages and terminal means being arranged so only one of said passages is immersed in a pool of said liquid in certain angular positions of said switch whereby said liquid electrically connects one terminal member with said terminal means first portion, and the other of said passages is immersed in a pool of said liquid in certain other angular positions of said switch whereby said liquid electrically connects the other terminal member with said terminal means first portion; said primary conductor-terminal in electrical contact with said terminal means second portion; said secondary conductor-terminal members individually in electrical contact with said terminal members; and an actuator handle for selectively angularly positioning said switch.

11. A four-way electrical liquid contact switch assembly comprising: a housing of electrical insulation material; a pair of primary conductor-terminal members; a pair of secondary conductor-terminal members; a pair of liquid contact switches, each of said switches comprising a pair of juxtaposed spaced opposed shallow dished shell terminal members of electrical conductive material being secured and electrically separated by an electrical insulating seal to form an enclosure; barrier means of electrical insulating material disposed within said enclosure between said terminal members and cooperating therewith to divide said enclosure into three spaced separate spaces for storage of electrically conductive liquid including a middle space and two end spaces; an electrical conducting terminal means extending through said barrier means from the interior to the exterior of said enclosure out of contact with said terminal members, said terminal means having a first portion extending into said middle space and a second portion extending to the exterior of said enclosure and arranged for electrical contact with an electrical conductor; said barrier means being provided with passage means arranged to connect said spaces in a preselected manner; a quantity of electrically conductive liquid disposed in said spaces; said passage means forming a passage between said middle space and an end space, and a separate non-aligned angularly displaced passage between said middle space and the other end space; said passages and terminal means being arranged so only one of said passages is immersed in a pool of said liquid in certain angular positions of said switch whereby said liquid electrically connects one terminal member with said terminal means first portion, and the other of said passages is immersed in a pool of said liquid in certain other angular positions of said switch whereby said liquid electrically connects the other terminal member with said terminal means first portion; said primary conductor-terminal members individually electrically connected to said terminal means second portions extending to the exterior of said enclosures; said secondary conductor-terminal members individually electrically connected to one of said terminal members of both of said switches; and an actuator handle for simultaneously angularly positioning both of said switches.

References Cited by the Examiner UNITED STATES PATENTS 12/1937 Payne 200152 12/1959 Cook et a1 200152 

1. A DUAL CIRCUIT CONTROLLING ELECTRICAL SWITCH COMPRISING: A PAIR OF SPACED OPPOSED JUXTAPOSED SHALLOW DISHED SHELL TERMINAL MEMBERS OF ELECTRICAL CONDUCTIVE MATERIAL BEING ELECTRICALLY SEPARATED AND CONNECTED AT THEIR ADJACENT PERIPHERIES BY AN ANNULAR ELECTRICAL INSULATING SEAL TO FORM AN ENCLOSURE; BARRIER MEANS OF ELECTRICAL INSULATING MATERIAL DISPOSED WITHIN SAID ENCLOSURE BETWEEN SAID TERMINAL MEMBERS AND COOPERATING THEREWITH TO DIVIDE SAID ENCLOSURE INTO THREE SPACED SEPARATE SPACES FOR STORAGE OF ELECTRICALLY CONDUCTIVE LIQUID INCLUDING A MIDDLE SPACE AND TWO END SPACES; AN ELECTRICAL CONDUCTING TERMINAL MEANS EXTENDING THROUGH SAID BARRIER MEANS FROM THE INTERIOR TO THE EXTERIOR OF SAID ENCLOSURE OUT OF CONTACT WITH SAID TERMINAL MEMBERS, SAID TERMINAL MEANS HAVING A FIRST PORTION EXTENDING INTO SAID MIDDLE SPACE ARRANGED TO BE CONTACTED BY SAID LIQUID AND A SECOND PORTION EXTENDING TO THE EXTERIOR OF SAID ENCLOSURE AND ARRANGED FOR ELECTRICAL CONTACT WITH AN ELECTRICAL CONDUCTOR; A QUANTITY OF ELECTRICALLY CONDUCTIVE LIQUID DISPOSED IN SAID SPACES; AND SAID BARRIER MEANS HAVING PASSAGE MEANS FORMING A PASSAGE EXTENDING BETWEEN SAID MIDDLE SPACE AND AN END SPACE, AND A SEPARATE DISPLACED PASSAGE EXTENDING BETWEEN SAID MIDDLE SPACE AND THE OTHER END SPACE; SAID PASSAGES AND TERMINAL MEANS BEING ARRANGED SO ONLY ONE OF SAID PASSAGES IS IMMERSED IN A POOL OF SAID LIQUID IN CERTAIN ANGULAR POSITIONS OF SAID SWITCH WHEREBY SAID LIQUID ELECTRICALLY CONNECTS ONE TERMINAL MEMBER WITH SAID TERMINAL MEANS FIRST PORTION, AND THE OTHER OF SAID PASSAGES IS IMMERSED IN A POOL OF SAID LIQUID IN CERTAIN OTHER POSITIONS OF SAID SWITCH WHEREBY SAID LIQUID ELECTRICALLY CONNECTS THE OTHER TERMINAL MEMBER WITH SAID TERMINAL MEANS FIRST PORTION. 